This lesson is a quick overview of the airway system in the United States.
Airways are the “highways in the sky” that connect each point in the United States. Airways tell air traffic controllers where we are going and how we are going to get there. Without airways, all aircraft would be free to amble their way across the country on their own and in their own direction.
Most current airways are “V” or Victor airways. Victor airways are defined by VOR type navigational aids and rely entirely on ground based navigation. This reliance on VORs means that victor airways have shorter segments that allow for proper signal reception between each station. Victor airways are designed with a large number of “intersections”, or points at which define intermediate segments of the route. These intersections allow for continuous course monitoring and for bends within the airway.
Due to the FAA’s desire to eliminate ground based navigation, new “T” routes are starting to be created. T routes use RNAV/GPS for navigation and do not rely on any ground based navigational aids. As a result, T routes can have much longer segments and go on a more direct path from point to point. T routes are depicted just the same as Victor airways, except for the “T” preceding the number designation and the new blue color of the airway.
It is also possible to fly off route direct from point to point. Direct flights need the approval of air traffic control and continuous radar contact. This is to ensure traffic separation and obstacle clearance. Obstacle clearance is assured by planning your flight to stay above the OROCA or Off Route Obstacle Clearance Altitude during your entire flight.
When filing a flight plan that involves airways, it is important to know that you can only join and exit an airway at a designated fix on the airway. Air traffic control must know where you plan to enter and exit the highway system so they can provide proper separation and sequencing of traffic. If traffic and workload permit, ATC can give you vectors to join an airway segment.
Hopefully this lesson helps!